import { IImageOptimizerOptions } from "../i-image-optimizer-options";
import { IIcoImageOptimizer } from "./i-ico-image-optimizer";
import { OptimizerResult } from "../../i-optimizer-result";
/**
 * An Image Optimizer that uses "to-ico" as its underlying implementation
 */
export declare class IcoImageOptimizer implements IIcoImageOptimizer {
    /**
     * Encodes an image using "to-ico".
     * If the image format is unsupported, an un-manipulated Buffer will be returned.
     * @param {IImageOptimizerOptions} options
     * @returns {Promise<OptimizerResult>}
     */
    optimize(options: IImageOptimizerOptions): Promise<OptimizerResult>;
    /**
     * Qualifies encoding the given input paths depending on its' kind
     * @param {IImageOptimizerOptions} options
     * @returns {Promise<OptimizerResult>}
     */
    private qualifyOptimization(options);
    /**
     * Encodes an image using "to-ico"
     * @param {IImageOptimizerOptions} options
     * @returns {Promise<Buffer>}
     */
    private runOptimizer(options);
    /**
     * Normalizes the input buffer to a 64x64, 8-bit per sample bit-depth PNG image
     * @param {IImageOptimizerOptions} options
     * @returns {Promise<Buffer>}
     */
    private getNormalizedPngBuffer(options);
}
